'It feels like the most powerful engine I've driven' - Button

Jenson Button says the latest generation of Formula One engines feel more powerful than any of the ones he has driven before even though headline bhp figures have not increased.

The new V6 turbos produce much more torque at lower revs than the previous naturally aspirated V8s and V10s Button has driven in the past, while the headline bhp figure of the engine and Energy Recovery System (ERS) remains similar to last year's V8s. After his first day behind the wheel of the McLaren, he said the acceleration out of slow corners makes the MP4-29 feel more powerful than the cars he has driven before.

"The power of the engine is nice," Button said. "It's very torquey, it feels like the most powerful engine I've driven. It obviously isn't in terms of outright power, but as a racing driver you feel the torque and power at the low speed and at 300 km/h you don't really feel the difference.

"It's coming out of the corners when you have so much torque that it's exciting. A lot to improve with the car in that area, but with so many tools at our disposal I know exactly how we can improve the car. I'm happy with our 'pretend' day one if you forget yesterday [when the McLaren didn't run].

"I think the positive thing is we have the ERS unit to fill in the gaps. I would say it's a very drivable engine at this early stage. There are moments when you are part throttle through the corner and there's all sorts going on. We're used to revs, we're used to downshifting but this is so, so different."

After missing the opening day due to an electrical issue, Button will spend another morning in the car on Thursday before handing over to team-mate Kevin Magnussen. After 43 laps at the wheel, Button said he was happy with the way the car felt so far.

"There's no horrible issues with the car itself," he said. "No big issues with the power unit in terms of how it delivers. So the basic car itself is where we want it to be. We always aim to have a good base because the way it will improve over the year and what we are going to add to this car, aerodynamically and with engine development, is massive. So having a good base is important.

"I enjoy driving this car. The power unit doesn't sound as good, that's a fact. It's not as exciting to hear from the outside, but when you're driving it it sounds good, we've got the turbo noise and the wastegate noise, which is actually a quite a nice change."